Digital library

  • Taking the ‘ew!’ out of seaweed, one dish at a time

    Slimy and sometimes smelly seaweed is not stuff most consumers dream of eating and Steve Backman of Magellan Aqua Farms gets that. So he plans to win North American taste buds over to this nutritious yet misunderstood crop one dish at a time.

    Backman farms scallops, sugar kelp and sea lettuce in New Brunswick’s Passamaquoddy Bay. The farm started out farming just scallops but bio-fouling on the shellfish led him to add sea urchins to the mix. “The urchins actually helped keep the cages clean. They were like little ‘scrubbing bubbles,’ and that was our first foray into IMTA,” says Backman.

    The farm’s progression to integrated multi-trophic aquaculture (IMTA) led  to conversations with Backman’s longtime friend, Dr Thierry Chopin, an IMTA advocate with the University of New Brunswick and founder of Chopin Coastal Health Solutions. Previous IMTA efforts had largely focused on fish farms. In their first year working together, they were mostly exploring kelp’s suitability to the site. The second year was spent finding the optimum depths for growing. Now, on their third year, they’re ready to expand.

    “We’ve been putting in more lines,” says Chopin. “It is growing gradually, but that’s the right approach. Rather than saying, ‘oh yeah, let’s put in some lines.’ We experimented and we’re scaling up.”

     “We are using the existing scallop lines so the scallops are growing below the kelp, and the buoys that  mark the scallop lines actually become the attachment points for the sea vegetables,” says Backman. “We capitalized on the efficiency of the physical assets that are out there. We never had to add any new equipment or any new infrastructure to grow the kelp, we just incorporated it into the existing scallop long lines.”

    Author(s): Matt Jones

  • Tapping Oceans' Bounty

    As demand for resources grow, the ocean may offer opportunities with fewer impacts than on land, so long as sustainable practices are ensured. Seaweed provides one such sustainable source for biofuels and other products, and with added bioremediation effects.

    Author(s): Jessica Marshall

  • Taredrivstoff kan bli storindustri

    Large scale cultivation of seaweed can be the start of a significant energy industry. SES is carrying out pilot tests outside Froya and preparing for scale-up.

    Author(s): Pål Bakken

  • Tarefarmene kommer (Seaweed farms are coming)

    The world's first modern seaweed farms being tested at Frøya.

    Author(s): Pål Bakken

  • Tasco: A Product of Ascophyllum nodosum Enhances Immune Response of Caenorhabditis elegans Against Pseudomonas aeruginosa Infection

    The effects of Tasco®, a product made from the brown seaweed (Ascophyllum nodosum) were tested for the ability to protect Caenorhabditis elegans against Pseudomonas aeruginosa infection. A water extract of Tasco® (TWE) reduced P. aeruginosa inflicted mortality in the nematode. The TWE, at a concentration of 300 µg/mL, offered the maximum protection and induced the expression of innate immune response genes viz.; zk6.7 (Lypases), lys-1 (Lysozyme), spp-1 (Saponin like protein), f28d1.3 (Thaumatin like protein), t20g5.7 (Matridin SK domain protein), abf-1 (Antibacterial protein) and f38a1.5 (Lectin family protein). Further, TWE treatment also affected a number of virulence components of the P. aeuroginosa and reduced its secreted virulence factors such as lipase, proteases and toxic metabolites; hydrogen cyanide and pyocyanin. Decreased virulence factors were associated with a significant reduction in expression of regulatory genes involved in quorum sensing, lasI, lasR, rhlI and rhlR. In conclusion, the TWE-treatment protected the C. elegans against P. aeruginosa infection by a combination of effects on the innate immunity of the worms and direct effects on the bacterial quorum sensing and virulence factors.

    Author(s): Balakrishnan Prithivira, Alan T. Critchley, Franklin Evans, Wajahatullah Khan, Saveetha Kandasamy

  • Taxonomic and ecological profile of 'green tide' species of VIva (Ulvales, Chlorophyta) in central Philippines

    Ulva spp. are common in the intertidal zones of the Philippines, but, at certain times, could over-proliferate producing blooms or `green tide' in some protected bays. In Mactan Island (Cebu), central Philippines, at least two species constitute the Ulva population, either as free-living or attached form. The one referred to in the literature as `Ulva lactuca' mainly consists of free-living population while the species referred to as Ulva reticulata consists mainly of attached population. Based on morphological and physiological characteristics, `U. lactuca' differs much from the descriptions of the species from its type locality in Europe in having a crumpled texture of blade, presence of tooth-like protuberances at the margins, thinner thallus (40–50 μm) and more pyrenoids per cell (two to four). The species referred to as `U. lactuca' in the Philippines therefore is a different species. Two morphotypes consisted the `U. lactuca' population from Mactan – a thick thallus and a thin thallus type. However, both morphotypes cultured under the same condition in the laboratory could transform into the same thin-thallus type observed in the field. `Green tide' caused by `U. lactuca' occur almost regularly in Station 1 of Mactan Island, reaching an average biomass of up to 2.6 kg wet wt m−2 (or 0.5 kg dry wt m−2). Ulva reticulata, although was less abundant in the rocky tidal zone at most times, reaching an average biomass of only up to 0.15 kg wet wt m−2 (or 0.03 kg dry wt m−2) had caused green tide in Station 2 around February–March. Reproductive structures were not observed in both Ulva species during the survey period suggesting that vegetative fragmentation is the main mode of propagation. Vegetative tissues excised from the thallus can be induced to release biflagellated large and small zooids.

    Author(s): Danilo B. Largo, Jose Sembranol, Masanori Hiraoka, Masao Ohno

  • Taxonomic assessment of North American species of the genera Cumathamnion, Delesseria, Membranoptera and Pantoneura (Delesseriaceae, Rhodophyta) using molecular data

    Evidence from molecular data supports the close taxonomic relationship of the two North Pacific species Delesseria decipiens and D. serrulata with Cumathamnion, up to now a monotypic genus known only from northern California, rather than with D. sanguinea, the type of the genus Delesseria and known only from the northeastern North Atlantic. The transfers of D. decipiens and D. serrulata into Cumathamnion are effected. Molecular data also reveal that what has passed as Membranoptera alata in the northwestern North Atlantic is distinct at the species level from northeastern North Atlantic (European) material; M. alata has a type locality in England. Multiple collections of Membranoptera and Pantoneura fabriciana on the North American coast of the North Atlantic prove to be identical for the three markers that have been sequenced, and the name Membranoptera fabriciana (Lyngbye) comb. nov. is proposed for them. Many collections of Membranoptera from the northeastern North Pacific (predominantly British Columbia), although representing the morphologies of several species that have been previously recognized, are genetically assignable to a single group for which the oldest name applicable is M. platyphylla.

    Author(s): Michael J. Wynne, Gary W. Saunders

  • Taxonomy of economic seaweeds - With reference to some Pacific species (Volume IV)

    In this section, the new Philippine species of Sargassum, described in English in the previous volume (and illustrated) are validated with Latin diagnoses. These 12 new species are added to the 50 or so "known" species in the large Philippine archipelago. 

    Two contributions in this volume address those species with furcately branching leaves, or compressed primary branches. The first, by Ajisaka, Noro, Trono, Chiang, and Yoshida, treats the characteristics of the species statistically, thus continuing some of the earlier perspective. The second paper, by Noro, Ajisaka, and Yoshida, places five species in the synonymy of other species, all common or widespread taxa. This indicates that by whatever means, a gradual understanding of the limits of the common Sargassum species is being reached. Inasmuch as some of these species are "old" (e.g., species of C. Agardh, who was among the first to distinguish species within this group), perhaps examination of "younger" species will show that the younger species had been named one or more times previously. 

    Author(s): Isabella A. Abbott

  • Taxonomy of economic seaweeds - With reference to some Pacific species (Volume V)

    The series of workshops of which this one was part rests on the conviction that progress in seaweed aquaculture and marine natural products chemistry will advance appreciably once the taxonomy of commercially interesting species is better understood. 

    California Sea Grant funded the first of these biennial workshops more than a decade ago - in 1984, at the University of Guam. From the first, Dr. Abbott served as organizer and motivator. Her vision was to bring together leading systematists from around the Pacific Rim to direct their knowledge and insight to the enormous ignorance that prevails about warm-water Pacific algae. She recognized that many of these eminent specialists were not being succeeded by younger generations and thus represented an irreplaceable resource. Further, she believed that the enthusiasm and dedication of workshop participants would overcome any difficulties presented by language and cultural differences.

    The progress made at these workshops has been considerable, and we at California Sea Grant, and our colleagues in the other Pacific Sea Grant Colleges, are pleased to have been able to play some small part in making them possible. 

    Author(s): Isabella A. Abbott

  • Taxonomy of economic seaweeds - With reference to some Pacific species (Volume VII)

    The original rationale behind this series of workshops was that progress in seaweed aquaculture and marine natural products chemistry would require that we better understand the taxonomy of commercially interesting species. Though this remains our primary goal, we have also come to appreciate that one of the most serious consequences of habitat destruction around the globe is loss of species diversity, including that of marine algae. Biodiversity has been defined as the collection of species (or distinct genetic entities), communities, and ecosystems occurring a geographically defined region. But describing changes in diversity over time, whether resulting from human activities or natural processes, require historical information based on rigorous species identification.

    Author(s): Isabella A. Abott

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